Colin Kaepernick played six seasons for the San Francisco 49ers as a quarterback in the NFL. Before a pre-season game in 2016 he kneeled during the anthem - as opposed to standing up - in order to protest against police brutality and racial ineaquality in the United States.
"I am not going to stand up to show pride in a flag for a country that oppresses black people and people of color."
After a season of controversy over his protest Kaepernick became a free agent in 2017. No NFL club has been willing to offer him a new contract since.